"""Alembic migration environment configuration."""

import asyncio
import os
from logging.config import fileConfig

from alembic import context
from sqlalchemy import pool, text
from sqlalchemy.engine import Connection
from sqlalchemy.ext.asyncio import async_engine_from_config

from noteflow.infrastructure.persistence.models import Base

# this is the Alembic Config object, which provides
# access to the values within the .ini file in use.
config = context.config

# Interpret the config file for Python logging.
# This line sets up loggers basically.
if config.config_file_name is not None:
    fileConfig(config.config_file_name)

# Import all models to ensure they're registered with Base.metadata
target_metadata = Base.metadata

if database_url := os.environ.get("NOTEFLOW_DATABASE_URL"):
    # Convert postgres:// to postgresql+asyncpg://
    if database_url.startswith("postgres://"):
        database_url = database_url.replace("postgres://", "postgresql+asyncpg://", 1)
    elif database_url.startswith("postgresql://"):
        database_url = database_url.replace("postgresql://", "postgresql+asyncpg://", 1)
    config.set_main_option("sqlalchemy.url", database_url)


def include_object(
    obj: object,
    name: str | None,
    type_: str,
    reflected: bool,
    compare_to: object | None,
) -> bool:
    """Filter objects for autogenerate."""
    # Only include objects in the noteflow schema
    if type_ == "table":
        schema = getattr(obj, "schema", None)
        return schema == "noteflow"
    return True


def run_migrations_offline() -> None:
    """Run migrations in 'offline' mode.

    This configures the context with just a URL
    and not an Engine, though an Engine is acceptable
    here as well.  By skipping the Engine creation
    we don't even need a DBAPI to be available.

    Calls to context.execute() here emit the given string to the
    script output.
    """
    url = config.get_main_option("sqlalchemy.url")
    context.configure(
        url=url,
        target_metadata=target_metadata,
        literal_binds=True,
        dialect_opts={"paramstyle": "named"},
        include_schemas=True,
        include_object=include_object,
        version_table_schema="public",
    )

    with context.begin_transaction():
        context.run_migrations()


def do_run_migrations(connection: Connection) -> None:
    """Execute migrations with the provided connection."""
    # Ensure the noteflow schema exists before Alembic tries to create its version table
    connection.execute(text("CREATE SCHEMA IF NOT EXISTS noteflow"))
    connection.commit()

    context.configure(
        connection=connection,
        target_metadata=target_metadata,
        include_schemas=True,
        include_object=include_object,
        version_table_schema="public",
    )

    with context.begin_transaction():
        context.run_migrations()


async def run_async_migrations() -> None:
    """Run migrations in async mode.

    Create an Engine and associate a connection with the context.
    """
    connectable = async_engine_from_config(
        config.get_section(config.config_ini_section, {}),
        prefix="sqlalchemy.",
        poolclass=pool.NullPool,
    )

    async with connectable.connect() as connection:
        await connection.run_sync(do_run_migrations)

    await connectable.dispose()


def run_migrations_online() -> None:
    """Run migrations in 'online' mode."""
    asyncio.run(run_async_migrations())


if context.is_offline_mode():
    run_migrations_offline()
else:
    run_migrations_online()
